Door closers



oCt- 23 1962 J. J. sELlNGER ETAL 3,059,269

DOOR CLOSERS Filed Dec. 24, 1959 /N VE/V T ORS JACOB J. SEI. /NGEPPETE/Q SEL/NGER A froR/vfys United States Patent 3,059,269 Patented Oct.23, 1962 3,059,269 DOOR CLOSERS Jacob J. Selnger and Peter Seliuger,both P.0. Box 73, R.R. 3, Hamilton, Ontario, Canada Filed Dec. 24, 1959,ser. No. 861,930 3 Claims. (Cl. 16-66) Our invention relates toimprovements in door actuating devices of the t-ype generally used forautomatically closing doors after they have been opened.

In general, the type of closing device over which this invention is animprovement, consists of a spring arrangement tending to swing the doorclosed, an air cylinder, a plunger moveable within the cylinder insynchronization with the door movement and compressing air within thecylinder as the door closes under the urge of the spring, the compressedair retarding the speed of movement of the door as it approaches theclosed position, and a valve or some similar arrangement for permittingand controlling the escape of compressed air from the cylinder as thedoor approaches its closed position. In other words the compressed airwithin the cylinder provides a snub to retard the door against slammingas would occur if the door was closed by an unopposed spring.

It will therefore be quite apparent that under the action of theforegoing described type of door closer, a manually released open door,under the urge of its spring at maximum tension, will immediately swingto close at maximum speed until snubbed by the air being compressedwithin the cylinder, and therefore in situations where it is desired tokeep the door open for even a relatively short period of time it isnecessary to provide some type of manually actuated device for retainingthe door in the open position and which must be manually released topermit the door to swing closed. Furthermore in this type of door closerthe spring loses most of its energy `when it has moved the door to thepoint of closure and wherein the air in the cylinder is at maximumcompression. Therefore, `if the escape of compressed air is not finelycontrolled the door either slams hard or lacks sufiicient momentum tocompletely close and latch.

The object of our invention is therefore to overcome the before reciteddefects by providing a spring urged door closer having a cylinder and adoor actuated plunger travelling therein,- but in which the movement ofthe plunger creates a vacuum within the cylinder when the door is fullyopened, the vacuum or suction retaining the door fully open for anydesired period of time depending upon controlled entrance of airgradually reducing the suction upon the plunger which is under the pullof the door closing spring. In this arrangement the entrance of air toreduce the vacuum or suction can be controlled to hold the door fullyopen for a predetermined period, and thus, for example, enable a motherto have sufficient time to wheel a baby carriage through lthe door waybefore the door commences to close.

Another object of the invention is to so control the admission of air tothe cylinder that in general circumstances wherein the door is notcompletely opened it will upon manual release immediately commence toclose.

A further and important object of the invention is to permit a free flowof air into the cylinder immediately prior to the moment the door shutsand whereby the door` is tightly closed and latched by the unopposedspring.

A still further object of the invention is to so control the expulsionof air from the closed end of the cylinder as the plunger moves towardsuch closed end upon the door being opened, that should the door beviolently swung, as under the force of a high wind, air compressing inthe cylinder under rapid plunger movement will,

due to its controlled expulsion, compress and provide a cushion againstthe door slamming open.

With the foregoing and other objects in view as shall appear ourinvention consists of a door closing device constructed and arranged allas hereinafter more particularly described and illustrated in theaccompanying drawings, in which:

FlG. l is a plan view of the door closer attached to the inner face of adoor which is partly open.

FG. 2'is an enlarged longitudinal cross-sectional view through thecylinder of the door closer.

FIG. 3 is an enlarged view of a metal casing mounted upon a face of thedoor and housing a tensioned spiral door closing spring, and

FIG. 4 is a vertical cross-sectional view taken through the line 4-4,FIG. 2.

Like characters of reference indicate similar parts in the several viewsof the drawings.

Our door closer comprises a cylinder 2 open at one end and having acylinder head 3 at its other end, and a plunger rod 6 extending throughan air seal such as the stuffing box 22 in the cylinder head 3 andattached to a plunger, as shall be hereinafter described.

4For mounting, the open end of the cylinder is secured within a ringy41A having a lug 9- pivotally mounted upon a bracket |10 arranged forfastening upon the door frame 12 or upon the adjacent Wall. To providethe necessary spring tension for closing the door 13 we preferably use astandard type coiled spring unit such as shown in FIG. 3 and comprisingan L-shaped bracket 14 attached to the face of the door and carrying afixed depending spindle `15 upon which a casing 16 is turnably mounted.The casing contains a tensioned spiral spring 17, one end of the springbeing anchored to the casing and the other end anchored to a flange :18upon the lower end of the spindle 15. The end of the plunger rod 6 isattached to the casing 16 and whereby the spring is wound to increaseits tension as the casing turns about the spindle under the swingingmotion of the plunger rod and cylinder pivotally mounted upon thebracket Il()` which is spaced away from the door hinge.

To provide the necessary arrangement for retaining the door open for apredetermined period and then closing the door, an adjustable air inletneedle valve [i9 is mounted within the cylinder head 3 and a secondadjustable needle valve 20 mounted within the cylinder wall apredetermined distance from the cylinder head. At a predetermined pointintermediately of the length of the stroke of the plunger and in thevicinity of the end of its inward movement the cylinder contains aninlet air iiow orice 211. 'In order to retain the plunger rod 6 inalignment with the cylinder when the rod is extended, the cylinder is ofgreater length than the length of travel of the plunger.

The plunger comprises a pair of spaced apart rigid discs 24 and 25freely fitting within the cylinder and mounted upon the end of theplunger rod 6i, and between which is positioned an O-ring 26 of thestandard type. The O-ring is formed of relatively soft rubber-likematerial and is of substantially the same outside diameter as the insidediameter of the cylinder 2. When the plunger is moved towards the closedend 3 of the cylinder the O-ring is pressed into the position shown infull lines and seals against the escape of air past the periphery of thedisc Z4, and conversely when the plunger is moved away from the closedend of the cylinder the O-ring is pressed into the position shown indotted lines and seals against the entrance of air into the cylinderpast the periphery of the disc 25. As it is necessary that air bepermitted to escape at a predetermined speed as the door is manuallyopened moving the plunger towards the closed end of the cylinder, thedisc Z4 contains an air escape orifice 27 of such a size that air hastime to escape from the closed end of the cylinder past the periphery ofthe disc and through the orifice 27 when the door is manually openedunder a normal motion. if, however, the door should be violently swungupon, as by the force of a wind storm, the air in the closed end of thecylinder has not a free enough passafre to be rapidly expelled under theaccelerated speed of movement of the plunger, consequently the aircompresses and forms a resilient snub against the door slamming open toits limit.

Operation Opening of the door .13 causes the plunger rod 6 and cylinder2 to swing about the bracket 16 with consequent coiling of the spiralspring 16 and movement of the plunger rod and plunger outwardly towardsthe sealed end of the cylinder, air escaping through the orifice 27 inthe plunger. The bracket 14 is so positioned on the door, that upon thedoor being fully swung open the plunger is in very close proximity tothe inner face of the cylinder head 3, so that upon release of the doora vacuum or greatly reduced air pressure is created between the plungerand the cylinder head as the O-ring Z6 is pressed against the face ofthe plunger disc 25 upon retraction of the plunger. Entrance of air intothe end space between the plunger and cylinder head 3 is controlled bythe setting of the needle valve 19 and whereby the speed of outwardmovement of the plunger and consequent initial closing movement of thedoor is governed and over which period the door remains practically wideopen. When the plunger moves outwardly a suiicient distance to uncoverthe needle valve 20 additional air is sucked through the valve behindthe plunger thus allowing the door to accelerate in closing speed untilthe air inlet orice 21 is uncovered just before the door completelycloses and whereby the snub of air suction through the valves =19 and2t) is obviated and the door closed and latched under the free force ofthe spring. 1t will be apparent that any open door period and speed ofclosure may be obtained by adjustment of the needle valves 19 andn 20.

From the foregoing description is will be apparent that we have provideda door closer which accomplishes the objects of our invention, and whilewe have shown our invention in its preferred form it is to be understoodthat we may make any changes deemed desirable without departing from thescope of the invention as set forth in the appended claims.

What We claim as our invention is:

1. An automatic door closer, comprising in combination, a bracket forattachment to a door jamb, an elongated tubular cylinder closed at oneend and open to the atmosphere at the other end and pivotally supportedat its open end by the bracket, a plunger moveable within the cylinder,the face of the plunger remote from the closed end of the cylinder beingconstantiy exposed to atmospheric pressure through the open end of thecylinder, a stufng box in the closed end of the cylinder, a

plunger rod secured to the plunger and protruding through the stuffingbox, a bracket for attachment to a door and to which the protruding endof the plunger rod is pivotally attached, a door closing spring urgingthe plunger away from the closed end of the cylinder, an adjustablevalve controlling entrance of air into the vacuum created in the closedend of the cylinder as the plunger is withdrawn therefrom under theurging of the door closing spring, a second adjustable Valvecommunieating with the interior of the cylinder and the atmosphere andpositioned intermediately of the length of the path of travel of theplunger to permit additional air to enter the cylinder as the plunger iswithdrawn past the second valve, and air ilow control means within theplunger for permitting the escape of air from the portion of thecylinder` between the plunger and the closed end of the cylinder as theplunger is moved towards the closed end against the resistance of thedoor closing spring, the plunger air ow control means permitting an airow through the plunger in its movement towards the closed end of thecylinder and sealing against an air ow through the plunger in itsmovement away from the closed end of the cylinder, the plunge air flowcontrol means comprising a pair of spaced apart discs freely Iittingwithin the bore of the cylinder and mounted upon the plunger rod, arelatively soft rubber-like ring of substantially the same outsidediameter as the inside diameter of the cylinder and positioned betweenthe discs to alternately contact either of the opposing faces of thediscs to provide an air seal between the contacted disc and the innerwall of the cylinder, the ring contacting the face of the disc remotefrom the closed end of the cylinder as the plunger moves towards theclosed end of the cylinder and contacting the face of the disc adjacentto the closed end of the cylinder as the plunger moves away from theclosed end of the cylinder, the disc remote from the closed end of thecylinder having an air escape orice therein and through which air isexpelled from the closed end of the cylinder under the movement of theplunger towards the closed end of the cylinder.

2. A door closer as dened in claim 1, wherein the orice in the disc isof only suicient size to permit free escape of air under normal speed ofmovement of the plunger towards the closed end of the cylinder when thedoor is manually opened but of insufficient size to permit freeexpulsion of air under plunger movement at a speed greater than suchnormal speed.

3. A door closer as defined in claim 2 wherein the cylinder contains anair inlet orifice past which the plunger moves and positioned inproximity to the extremity of the movement of the plunger away from theclosed end of the cylinder.

References Cited in the le of this patent UNITED STATES PATENTS 37 0,468Griiling et al Sept. 27, 1887 476,932 Shrawder June 14, 1892 2,897,534Pickerell Y V Aug. 4, 195 9

